fix: pin versions

[ArthurTonial]

Disclaimer: Do not include SAP-internal or customer-specific information in this PR (e.g. internal system URLs, customer names, tenant IDs, or confidential configurations). This is a public repository.

Description

Replaces ~= (compatible release) pin specifiers with explicit >=x,<N major-version ranges for all runtime dependencies in pyproject.toml. This makes upper bounds intentional and documented rather than an implicit side-effect of the ~= operator.

Also bumps the protobuf lower bound from >=4.25.0 to >=5.0.0.

Related Issue

N/A

Type of Change

Please check the relevant option:

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update
• Code refactoring
• Dependency update

How to Test

1. Run uv sync from a clean environment — resolution should succeed with no conflicts.
2. Run the full test suite: uv run pytest
3. Verify all dependency versions in uv.lock fall within the new declared ranges.

Checklist

Before submitting your PR, please review and check the following:

• I have read the Contributing Guidelines
• I have verified that my changes solve the issue
• I have added/updated automated tests to cover my changes
• All tests pass locally
• I have verified that my code follows the Code Guidelines
• I have updated documentation (if applicable)
• I have added type hints for all public APIs
• My code does not contain sensitive information (credentials, tokens, etc.)
• I have followed Conventional Commits for commit messages

Breaking Changes

None.